... That after the caulk is laid, to spray the 'area' then? I've done the job somewhat in this manner. The difference is I lay down the caulk then dip my fingertip into some soapy water and run the tip along the bead. This smoothes out the bead.
On the point being made, I wouldn't lay any 'spray' down first before caulking because the soapy water will most likely prevent the caulk from adhearing. After-the-laydown, I guess you could spray but in my mind, it seems like over-kill. Try the dip-trick if you're so inclined.